Folding chair

ABSTRACT

The present application provides a folding chair including a first backrest tube, on which a first through-hole bracket is sleeved; a second backrest tube, on which a second through-hole bracket is sleeved; a first connecting component connecting the first backrest tube and the second backrest tube; a first intersecting tube including a first front-leg tube and a first rear-leg tube which are articulated to one another; a second intersecting tube including a second front-leg tube and a second rear-leg tube which are articulated to one another; and a second connecting component connecting the first intersecting tube and the second intersecting tube. The folding chair further comprises a first waist-rest portion and a second waist-rest portion which are symmetrically arranged, and are configured to fit a waist curve when the folding chair is unfolded.

The present application claims the benefit of priority to Chinese Patent Application No. 201310201573.6 titled “FOLDING CHAIR”, filed with the Chinese State Intellectual Property Office on May 27, 2013, which is hereby incorporated by reference in its entirety.

The present application claims the benefit of priority to Chinese Patent Application No. 201320295105.5 titled “FOLDING CHAIR”, filed with the Chinese State Intellectual Property Office on May 27, 2013, which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present application relates to a chair, and particularly relates to a folding chair.

BACKGROUND OF THE INVENTION

Folding chair is a portable and foldable chair, which is convenient to move and saves space. A common folding chair mainly consists of thickened steel tubes and oxford cloth. The surfaces of the steel tubes are treated through plastic spraying, thus are anti-rust and artistic, and critical parts of the steel tubes that are subjected to force are dealt with mechanical treatment, such that the bearing capability is greatly improved. Specifications of the oxford cloth mainly include 600D or 800D. Most of folding chairs have a double-layer cloth structure to improve service life and comfortableness of the chair seat. Folding and connecting parts are connected by galvanized rivets and virgin plastic members. According to characteristics of different products, a string bag for cup, an operating panel, a storage bag, a foot rest, a sunshade and other designs can be additionally provided. For the folding chair using the double-layer cloth structure, the service life of the chair seat thereof is as long as a chair seat made by plastic injection, and the above folding chair is more convenient to carry, thus is a kind of folding chair frequently used indoors and outdoors.

As shown in FIG. 1, the folding chair includes two backrest tubes (001, 002), three sets of intersecting tubes (003, 004, 005, 006, 007, 008), two armrest tubes (009, 010), four lower brackets (013, 014, 015, 016), two armrest brackets (017, 018) and two through-hole brackets (011, 012). In using this folding chair, the upper intersecting tube 003, the lower intersecting tube 004, the armrest tube 010 and the armrest tube 009 are unfolded, and then the upper intersecting tube 007, the lower intersecting tube 008, the upper intersecting tube 005 and the lower intersecting tube 006 are unfolded, and at this time the folding chair can be used. During folding, the folding chair can be folded by folding the armrest tube 010 and the armrest tube 009 inward.

In order to facilitate the folding process, the above backrest tubes of the folding chair are straight tubes, thus when a user is sitting on the folding chair, the waist of the user is not supported, and when sitting on the folding chair for a long time, the waist of the user is apt to concave downward which may cause pain in the waist of the user.

Therefore, a technical problem desired to be solved by the person skilled in the art is to provide a folding chair which can make the user feel more comfortable.

SUMMARY OF THE INVENTION

In view of this, the present application provides a folding chair for improving comfortableness for a user.

For achieving the above object, the present application provides a technical solution as follows.

A folding chair, including:

a first backrest tube, on which a first through-hole bracket is sleeved; a second backrest tube, on which a second through-hole bracket is sleeved; a first connecting component connecting the first backrest tube and the second backrest tube; a first intersecting tube including a first front-leg tube and a first rear-leg tube which are articulated to one another; a second intersecting tube including a second front-leg tube and a second rear-leg tube which are articulated to one another; and a second connecting component connecting the first intersecting tube and the second intersecting tube; wherein the folding chair further comprises a first waist-rest portion and a second waist-rest portion which are symmetrically arranged, and are configured to fit a waist curve when the folding chair is unfolded.

the first connecting component includes a first upper connecting tube and a first lower connecting tube which are articulated to one another at middle portions thereof; and the second connecting component includes a second upper connecting tube and a second lower connecting tube which are articulated to one another at middle portions thereof.

The first front-leg tube includes a top end articulated to the first through-hole bracket and a bottom end fixedly provided with a third lower bracket; and the first rear-leg tube includes a top end provided with a first upper bracket and a bottom end articulated to the first backrest tube via a first lower bracket.

The second front-leg tube includes a top end articulated to the second through-hole bracket and a bottom end fixedly provided with a fourth lower bracket; and the second rear-leg tube includes a top end provided with a second upper bracket and a bottom end articulated to the second backrest tube via a second lower bracket.

The first upper connecting tube includes a top end articulated to the first through-hole bracket and a bottom end articulated to the second lower bracket; and the first lower connecting tube includes a top end articulated to the second through-hole bracket and a bottom end articulated to the first lower bracket.

The second upper connecting tube includes a top end articulated to the first upper bracket and a bottom end articulated to the fourth lower bracket; and the second lower connecting tube includes a top end articulated to the second upper bracket and a bottom end articulated to the third lower bracket.

The top end of the second upper connecting tube is extended to form a first armrest portion, and the top end of the second lower connecting tube is extended to form a second armrest portion.

The folding chair further includes a first waist-rest tube and a second waist-rest tube; and the first waist-rest portion is an arc-shaped protrusion provided on an upper portion of the first waist-rest tube, and the second waist-rest portion is an arc-shaped protrusion provided on an upper portion of the second waist-rest tube.

The first waist-rest tube includes a bottom end articulated to a first sliding block, and a middle portion articulated to an end, close to the first through-hole bracket, of the first upper connecting tube, and the first sliding block is sleeved on an end, close to the first lower bracket, of the first lower connecting tube.

The second waist-rest tube includes a bottom end articulated to a second sliding block, and a middle portion articulated to an end, close to the second through-hole bracket, of the first lower connecting tube, and the second sliding block is sleeved on an end, close to the second lower bracket, of the first upper connecting tube.

The first waist-rest tube includes a bottom end articulated to a first sliding block, and a middle portion articulated to an end, close to the first through-hole bracket, of the first front-leg tube, and the first sliding block is sleeved on an end, close to the first lower bracket, of the first rear-leg tube.

The second waist-rest tube includes a bottom end articulated to a second sliding block, and a middle portion articulated to an end, close to the second through-hole bracket, of the second front-leg tube, and the second sliding block is sleeved on an end, close to the second lower bracket, of the second rear-leg tube.

The first waist-rest tube includes a bottom end articulated to a first sliding block, and a middle portion articulated to an end, close to the first through-hole bracket, of the first front-leg tube, and the first sliding block is sleeved on the first backrest tube.

The second waist-rest tube includes a bottom end articulated to a second sliding block, and a middle portion articulated to an end, close to the second through-hole bracket, of the second front-leg tube, and the second sliding block is sleeved on the second backrest tube.

The folding chair further includes an oxford cloth covered on the first backrest tube, the second backrest tube and the second connecting component.

The first waist-rest portion includes a first woven strip and a first steel sheet, the first steel sheet is bent at a preset angle by the first woven strip, and the first waist-rest portion is fixed at a part, corresponding to a backrest of the folding chair, of the oxford cloth.

The second waist-rest portion includes a second woven strip and a second steel sheet, the second steel sheet is bent at a preset angle by the second woven strip, and the second waist-rest portion is fixed at a part, corresponding to the backrest of the folding chair, of the oxford cloth.

The first waist-rest portion is a steel sheet having a certain curvature and is fixed at a part, corresponding to a backrest of the folding chair, of the oxford cloth; and the second waist-rest portion is a steel sheet having a certain curvature, and is fixed at a part, corresponding to the backrest of the folding chair, of the oxford cloth.

The first waist-rest portion is an arc-shaped protrusion provided on an end, close to the first backrest tube, of the first front-leg tube, and the second waist-rest portion is an arc-shaped protrusion provided on an end, close to the second backrest tube, of the second front-leg tube;

a top end of the first front-leg tube is articulated to the first through-hole bracket, and a top end of the second front-leg tube is articulated to the second through-hole bracket; and

a first U-shaped member is sleeved on the first rear-leg tube, and a bottom end of the first backrest tube is articulated to the first U-shaped member; and a second U-shaped member is sleeved on the second rear-leg tube, and a bottom end of the second backrest tube is articulated to the second U-shaped member.

A top end of the first rear-leg tube is extended to form a first armrest portion, and a top end of the second rear-leg tube is extended to form a second armrest portion.

The folding chair further includes a first seat tube articulated to the bottom end of the first backrest tube and the first front-leg tube; a second seat tube articulated to the bottom end of the second backrest tube and the second front-leg tube; a first retractable tube including one end articulated to the first seat tube and the other end articulated to the first front-leg tube; and a second retractable tube including one end articulated to the second seat tube and the other end articulated to the second front-leg tube.

The first upper connecting tube includes a top end articulated to the first through-hole bracket, and a bottom end articulated to the second rear-leg tube; and the first lower connecting tube includes a top end articulated to the second through-hole bracket, and a bottom end articulated to the first rear-leg tube.

The second upper connecting tube includes a top end articulated to an outer retractable tube of the first retractable tube, and a bottom end articulated to an inner retractable tube of the second retractable tube; and the second lower connecting tube includes a top end articulated to an outer retractable tube of the second retractable tube, and a bottom end articulated to an inner retractable tube of the first retractable tube.

The outer retractable tube of the first retractable tube is articulated to the first seat tube via a third U-shaped member, and the inner retractable tube of the first retractable tube is articulated to the first front-leg tube via a pin; and the outer retractable tube of the second retractable tube is articulated to the second seat tube via a fourth U-shaped member, and the inner retractable tube of the second retractable tube is articulated to the second front-leg tube via a pin.

The arc-shaped protrusion on the first front-leg tube and the first front-leg tube are welded to form an integral structure; and the arc-shaped protrusion on the second front-leg tube and the second front-leg tube are welded to form an integral structure.

The first front-leg tube and the arc-shaped protrusion on the first front-leg tube are formed by bending a tube member, and the second front-leg tube and the arc-shaped protrusion on the second front-leg tube are formed by bending a tube member.

The arc-shaped protrusion on the first front-leg tube is formed by bending a tube member and includes two ends welded on the first front-leg tube; and the arc-shaped protrusion on the second front-leg tube is formed by bending a tube member and includes two ends welded on the second front-leg tube.

From the above technical solution, it can be seen that, in the folding chair according to the present application, a first waist-rest portion and a second waist-rest portion are additionally provided and can fit a waist curve of a human body. In using, the folding chair is unfolded, and under the action of the first waist-rest portion and the second waist-rest portion, a protruded portion is formed on the oxford cloth to properly support the waist of a user, so as to prevent the waist from concaving downward and make the user feel more comfortable.

BRIEF DESCRIPTION OF THE DRAWINGS

For more clearly illustrating embodiments of the present application or the technical solution in the prior art, drawings referred to describe the embodiments or the prior art will be briefly described hereinafter. Apparently, the drawings in the following description are only several embodiments of the present application, and for the person skilled in the art other drawings may be obtained based on these drawings without any creative efforts.

FIG. 1 is a perspective schematic view showing the structure of a folding chair in the prior art;

FIG. 2 is an exploded schematic view of a folding chair according to a first embodiment of the present application;

FIG. 3 is a perspective schematic view showing the structure of the folding chair according to the first embodiment of the present application;

FIG. 4 is a side schematic view showing the structure of the folding chair according to the first embodiment of the present application;

FIG. 5 is a schematic view showing the folding process of the folding chair according to the first embodiment of the present application;

FIG. 6 is a schematic view showing the folding chair in folded state according to the first embodiment of the present application;

FIG. 7 is an exploded schematic view of a folding chair according to a second embodiment of the present application;

FIG. 8 is a perspective schematic view showing the structure of the folding chair according to the second embodiment of the present application;

FIG. 9 is a side schematic view showing the structure of the folding chair according to the second embodiment of the present application;

FIG. 10 is a schematic view showing the folding process of the folding chair according to the second embodiment of the present application;

FIG. 11 is a schematic view showing the folding chair in folded state according to the second embodiment of the present application;

FIG. 12 is an exploded schematic view of a folding chair according to a third embodiment of the present application;

FIG. 13 is a perspective schematic view showing the structure of the folding chair according to the third embodiment of the present application;

FIG. 14 is a side schematic view showing the structure of the folding chair according to the third embodiment of the present application;

FIG. 15 is a schematic view showing the folding process of the folding chair according to the third embodiment of the present application;

FIG. 16 is a schematic view showing the folding chair in folded state according to the third embodiment of the present application;

FIG. 17 is an exploded schematic view of a folding chair according to a fourth embodiment of the present application;

FIG. 18 is a perspective schematic view showing the structure of the folding chair according to the fourth embodiment of the present application;

FIG. 19 is a side schematic view showing the structure of the folding chair according to the fourth embodiment of the present application;

FIG. 20 is a schematic view showing the folding process of the folding chair according to the fourth embodiment of the present application;

FIG. 21 is a schematic view showing the folding chair in folded state according to the fourth embodiment of the present application;

FIG. 22 is a perspective schematic view showing the structure of a folding chair according to a fifth embodiment of the present application;

FIG. 23 is an exploded schematic view showing the structure of the folding chair according to the fifth embodiment of the present application;

FIG. 24 is a schematic view showing the folding process of the folding chair according to the fifth embodiment of the present application;

FIG. 25 is a schematic view showing the folding chair in folded state according to the fifth embodiment of the present application;

FIG. 26 is a perspective schematic view showing the structure of a folding chair according to a sixth embodiment of the present application;

FIG. 27 is an exploded schematic view showing the structure of the folding chair according to the sixth embodiment of the present application;

FIG. 28 is a schematic view showing the folding process of the folding chair according to the sixth embodiment of the present application;

FIG. 29 is a schematic view showing the folding chair in folded state according to the sixth embodiment of the present application;

FIG. 30 is a perspective schematic view showing the structure of a folding chair according to a seventh embodiment of the present application;

FIG. 31 is an exploded schematic view showing the structure of the folding chair according to the seventh embodiment of the present application;

FIG. 32 is a schematic view showing the folding process of the folding chair according to the seventh embodiment of the present application; and

FIG. 33 is a schematic view showing the folding chair in folded state according to the seventh embodiment of the present application;

wherein, the corresponding relationships between the reference numerals in FIG. 1 and the components are as follows:

001 a backrest tube; 002 a backrest tube; 003 an upper intersecting tube; 004 a lower intersecting tube; 005 an upper intersecting tube; 006 a lower intersecting tube; 007 an upper intersecting tube; 008 a lower intersecting tube; 009 an armrest tube; 010 an armrest tube; 011 a through-hole bracket; 012 a through-hole bracket; 013 a lower bracket; 014 a lower bracket; 015 a lower bracket; 016 a lower bracket; 017 an armrest bracket; and 018 an armrest bracket.

And, the corresponding relationships between the reference numerals in FIGS. 2 to 33 and the components are as follows:

101 a first backrest tube; 102 a second backrest tube; 103 a first upper connecting tube; 104 a first lower connecting tube; 105 a first front-leg tube; 106 a first rear-leg tube; 107 a second front-leg tube; 108 a second rear-leg tube; 109 a second upper connecting tube; 110 a second lower connecting tube; 111 a first through-hole bracket; 112 a second through-hole bracket; 113 a first lower bracket; 114 a second lower bracket; 115 a third lower bracket; 116 a fourth lower bracket; 117 a first upper bracket; 118 a second upper bracket; 119 a first backrest tube; 120 a second backrest tube; 121 a first sliding block; 122 a second sliding block; 123 a first waist-rest portion; 124 a second waist-rest portion; 131 a first seat tube; 132 a second seat tube; 133 a first retractable tube; 134 a second retractable tube; 135 a first U-shaped member; 136 a second U-shaped member; 137 a third U-shaped member; 138 a fourth U-shaped member; 139 a first arc-shaped protrusion; and 140 a second arc-shaped protrusion.

DETAILED DESCRIPTION OF THE INVENTION

For those skilled in the art to better understand technical solutions of the present application, the present application will be described in detail in conjunction with drawings and embodiments hereinafter.

A folding chair provided by the present application includes a first backrest tube, on which a first through-hole bracket is sleeved; a second backrest tube, on which a second through-hole bracket is sleeved; a first connecting component connecting the first backrest tube and the second backrest tube; a first intersecting tube including a first front-leg tube and a first rear-leg tube which are articulated to one another; a second intersecting tube including a second front-leg tube and a second rear-leg tube which are articulated to one another; and a second connecting component connecting the first intersecting tube and the second intersecting tube. The folding chair further includes a first waist-rest portion and a second waist-rest portion which are symmetrically arranged and may fit a waist curve when the folding chair is unfolded.

Specifically, the first connecting component includes a first upper connecting tube and a first lower connecting tube which are articulated to one another at middle portions thereof; and the second connecting component includes a second upper connecting tube and a second lower connecting tube which are articulated to one another at middle portions thereof.

In the above folding chair, two waist-rest portions are provided, such that when the folding chair is unfolded, the waist-rest portions can fit a physiological curve of the waist of a human body so as to support the waist and improve comfortableness for a user.

As shown in FIGS. 2 to 21, the folding chair according to the embodiments of the present application includes a first backrest tube 101, on which a first through-hole bracket 111 is sleeved; a second backrest tube 102, on which a second through-hole bracket 112 is sleeved; a first connecting component connecting the first backrest tube 101 and the second backrest tube 102; a first intersecting tube connecting a first upper bracket 117 and the first backrest tube 101; a second intersecting tube connecting a second upper bracket 118 and the second backrest tube 102; a second connecting component connecting the first upper bracket 117 and the second upper bracket 118; and an oxford cloth covered on the first backrest tube 101, the second backrest tube 102 and the second connecting component. The folding chair further includes a first waist-rest portion and a second waist-rest portion which are symmetrically arranged and are located between the first backrest tube 101 and the second backrest tube 102 to fit a waist curve when the folding chair is unfolded.

When the folding chair is unfolded, the oxford cloth is completely spread, and the oxford cloth supported by the first backrest tube and the second backrest tube forms a backrest of the folding chair, and the oxford cloth supported by the first intersecting tube, the second intersecting tube and the second connecting component forms a chair seat of the folding chair.

The folding chair according to the embodiments of the present application is additionally provided with the first waist-rest portion and the second waist-rest portion, and these two waist-rest portions can fit the waist curve. In using, when the folding chair is unfolded, a protruding portion is formed on the oxford cloth under the action of the first waist-rest portion and the second waist-rest portion, and the protruding portion can properly support the waist of the user, thereby having the function of supporting the waist and improving comfortableness for the user.

In the embodiments of the present application, the first connecting component and the second connecting component can be rigid connecting components, such as a connecting tube. Taking the first connecting component as an example, two ends of the connecting tube are respectively fixed to the first backrest tube 101 and the second backrest tube 102, and at this time, the first backrest tube 101 and the second backrest tube 102 can not perform a folding action, and only the first intersecting tube and the second intersecting tube can perform the folding action. Furthermore, the first connecting component and the second connecting component can be components that can be unfolded and folded, such as connecting sheets with ends thereof being overlapped and articulated. Specifically, one of the connecting sheets is articulated to the first backrest tube 101, and the other connecting sheet is articulated to the second backrest tube 102. And, an elastic component having a clamping function is provided at articulated parts of the connecting sheets, and when it is required to fold the first connecting sheet and the second connecting sheet, the elastic component is pulled outward, then the first connecting sheet and the second connecting sheet can be folded.

In the folding chair according to the embodiments of the present application, the first intersecting tube includes a first front-leg tube 105 and a first rear-leg tube 106 which are articulated to one another at middle portions thereof. Specifically, a top end of the first front-leg tube 105 is articulated to the first through-hole bracket 111, a top end of the first rear-leg tube 106 is provided with the first upper bracket 117, a bottom end of the first rear-leg tube 106 is articulated to the first backrest tube 101. The second intersecting tube includes a second front-leg tube 107 and a second rear-leg tube 108 which are articulated to one another at middle portions thereof. Specifically, a top end of the second front-leg tube 107 is articulated to the second through-hole bracket 112, a top end of the second rear-leg tube 108 is provided with the second upper bracket 118, and a bottom end of the second rear-leg tube 108 is articulated to the second backrest tube 102. Of course, structures of the first intersecting tube and the second intersecting tube in the embodiments of the present application can be changed depending on a specific application situation. For example, one of the intersecting tubes can be designed to have an arc-shaped structure for functioning as an armrest.

The intersecting tubes and the backrest tubes described hereinabove can achieve connections between tube members by their own structure, or achieve connections between tube members by means of brackets. For example, the bottom end of the first rear-end tube 106 is articulated to the first backrest tube 101 via a first lower bracket 113; a bottom end of the first front-leg tube 105 is fixedly provided with a third lower bracket 115; the bottom end of the second rear-leg tube 108 is articulated to the second backrest tube 102 via a second lower bracket 114; and a bottom end of the second front-leg tube 107 is fixedly provided with a fourth lower bracket 116.

When the first intersecting tube is connected to the second intersecting tube via the above brackets, the first connecting component includes a first upper connecting tube 103 and a first lower connecting tube 104 which are articulated to one another at middle portions thereof. Specifically, a top end of the first upper connecting tube 103 is articulated to the first through-hole bracket 111, a bottom end of the first upper connecting tube 103 is articulated to the second lower bracket 114, a top end of the first lower connecting tube 104 is articulated to the second through-hole bracket 112, and a bottom end of the first lower connecting tube 104 is articulated to the first lower bracket 113. The second connecting component includes a second upper connecting tube 109 and a second lower connecting tube 110 which are articulated to one another at middle portions thereof. Specifically, a top end of the second upper connecting tube 109 is articulated to the first upper bracket 117, a bottom end of the second upper connecting tube 109 is articulated to the fourth lower bracket 116, a top end of the second lower connecting tube 110 is articulated to the second upper bracket 118, and a bottom end of the second lower connecting tube 110 is articulated to the third lower bracket 115.

The above brackets can have the same structure or different structures. Preferably, in the embodiments of the present application, the above brackets are made to have the same structure to improve universality of the brackets, such that when one of the brackets is broken, the broken bracket can be replaced conveniently. A main body of each of the brackets is provided with a mounting hole for accommodating the backrest tube, and an articulating portion to be articulated with the tube members. Each bracket has two articulating portions, the two articulating portions are arranged at 90 degree angle to each another, and the articulating portion has a through hole for accommodating a rivet. Taking the first lower bracket 113 mounted at the bottom portion of the first backrest tube 101 as an example, the first backrest tube 101 is fixed in the mounting hole of the first lower bracket 113, the first rear-leg tube 106 is articulated to a first articulating portion of the first lower bracket 113, and the first lower connecting tube 104 is articulated to a second articulating portion of the first lower bracket 113. Taking the fourth lower bracket 116 as an example, since it is not required to mount a backrest tube in the fourth lower bracket 116, the corresponding mounting hole is idle, and a first articulating portion of the fourth lower bracket 116 is articulated to the bottom end of the second upper connecting tube 109, and a second articulating portion of the fourth lower bracket 116 is articulated to the bottom end of the second front-leg tube 107.

In the above second connecting component, the top end of the second upper connecting tube 109 is extended to form a first armrest portion, and the top end of the second lower connecting tube 110 is extended to form a second armrest portion. Due to the arrangement of the armrest portions, a user can put his hands on the armrest portions.

In addition to the articulating portions to be articulated with the intersecting tubes, both of the first upper bracket 117 and the second upper bracket 118 further has a groove for supporting the second upper connecting tube or the second lower connecting tube accordingly.

The embodiments of the present application further provide various structures and specific mounting manners of the first waist-rest portion and the second waist-rest portion.

In the folding chair according to the first embodiment of the present application as shown in FIGS. 2 to 6, the first waist-rest portion is an arc-shaped protrusion of a first waist-rest tube 119. Specifically, a bottom end of the first waist-rest tube 119 is articulated to a first sliding block 121, a middle portion of the first waist-rest tube 119 is articulated to an end, close to the first through-hole bracket 111, of the first front-leg tube 105, and the first sliding block 121 is sleeved on an end, close to the first lower bracket 113, of the first rear-leg tube 106. The second waist-rest portion is an arc-shaped protrusion of a second waist-rest tube 120. Specifically, a bottom end of the second waist-rest tube 120 is articulated to a second sliding block 122, a middle portion of the second waist-rest tube 120 is articulated to an end, close to the second through-hole bracket 112, of the second front-leg tube 107, and the second sliding block 122 is sleeved on an end, close to the second lower bracket 114, of the second rear-leg tube 108.

In using, the first backrest tube 101, the second backrest tube 102, the second upper connecting tube 109 and the second lower connecting tube 110 are moved outward so as to unfold the folding chair. As shown in FIG. 4, under the action of the arc-shaped protrusions on the first waist-rest tube 119 and the second waist-rest tube 120, a protruding portion is formed on the oxford cloth to properly support the waist of the user, so as to improve comfortableness for a user. During folding, as shown in FIGS. 5 and 6, the folding process can be achieved in only one step by pulling the second front-leg tube 107 and the second rear-leg tube 108 inward.

As shown in FIGS. 7 to 11, in a folding chair according to a second embodiment of the present application, the first waist-rest portion is an arc-shaped protrusion of the first waist-rest tube 119. Specifically, a bottom end of the first waist-rest tube 119 is articulated to a first sliding block 121, a middle portion of the first waist-rest tube 119 is articulated to an end, close to the first through-hole bracket 111, of the first upper connecting tube 103, and the first sliding block 121 is sleeved on an end, close to the first lower bracket 113, of the first lower connecting tube 104. The second waist-rest portion is an arc-shaped protrusion of the second waist-rest tube 120. Specifically, a bottom end of the second waist-rest tube 120 is articulated to a second sliding block 122, a middle portion of the second waist-rest tube 120 is articulated to an end, close to the second through-hole bracket 112, of the first lower connecting tube 104, and the second sliding block 122 is sleeved on an end, close to the second lower bracket 114, of the first upper connecting tube 103.

In using, the first backrest tube 101, the second backrest tube 102, the second upper connecting tube 109 and the second lower connecting tube 110 are moved outward so as to unfold the folding chair. As shown in FIG. 9, under the action of the arc-shaped protrusions on the first waist-rest tube 119 and the second waist-rest tube 120, a protruding portion is formed on the oxford cloth to properly support the waist of the user, so as to improve comfortableness for a user. During folding, as shown in FIGS. 10 and 11, the folding process can be achieved in only one step by pulling the second front-leg tube 107 and the second rear-leg tube 108 inward.

In addition, the embodiments of the present application further provide a folding chair. In the folding chair, the first waist-rest portion is an arc-shaped protrusion on the first waist-rest tube 119. Specifically, a bottom end of the first waist-rest tube 119 is articulated to a first sliding block 121, a middle portion of the first waist-rest tube 119 is articulated to an end, close to the first through-hole bracket 111, of the first front-leg tube 105, and the first sliding block 121 is sleeved on the first backrest tube 101. The second waist-rest portion is an arc-shaped protrusion of the second waist-rest tube 120. Specifically, a bottom end of the second waist-rest tube 120 is articulated to a second sliding block 122, a middle portion of the second waist-rest tube 120 is articulated to an end, close to the second through-hole bracket 112, of the second front-leg tube 107, and the second sliding block 122 is sleeved on the second backrest tube 102.

In using, the first backrest tube 101, the second backrest tube 102, the second upper connecting tube 109 and the second lower connecting tube 110 are moved outward so as to unfold the folding chair. Under the action of the arc-shaped protrusions on the first waist-rest tube 119 and the second waist-rest tube 120, a protruding portion is formed on the oxford cloth to properly support the waist of the user, so as to improve comfortableness for a user. During folding, the folding process can be achieved in only one step by pulling the second front-leg tube 107 and the second rear-leg tube 108 inward.

In the above various embodiments, the first sliding block 121 and the second sliding block 122 each include a cylindrical portion and a U-shaped connecting member. The cylindrical portion is used to be sleeved on the corresponding member. The U-shaped connecting member is used to be articulated with the waist-rest tube.

According to various locations of the first waist-rest tube 119 and the second waist-rest tube 120, the waist-rest tubes are bent in different ways. When the first waist-rest tube 119 and the second waist-rest tube 120 are respectively mounted on the first intersecting tube and the second intersecting tube, the folding chair has a relatively smaller packaging volume.

As shown in FIGS. 12 to 16, in a folding chair according to a third embodiment of the present application, the first waist-rest portion 123 includes a first woven strip and a first steel sheet, the first steel sheet is bent at a preset angle by the first woven strip, and the first waist-rest portion 123 is fixed to a part, corresponding to the backrest of the folding chair, of the oxford cloth. The second waist-rest portion 124 includes a second woven strip and a second steel sheet, the second steel sheet is bent at a preset angle by the second woven strip, and the second waist-rest portion 124 is fixed to a part, corresponding to the backrest of the folding chair, of the oxford cloth.

In using, the first backrest tube 101, the second backrest tube 102, the second upper connecting tube 109 and the second lower connecting tube 110 are moved outward so as to unfold the folding chair. Under the action of the first waist-rest portion 123 and the second waist-rest portion 124, a protruding portion is formed on the oxford cloth to properly support the waist of the user, so as to improve comfortableness for a user. During folding, the folding process can be achieved in only one step by pulling the second front-leg tube 107 and the second rear-leg tube 108 inward.

As shown in FIGS. 17 to 21, in a folding chair according to a fourth embodiment of the present application, the first waist-rest portion 123 is a steel sheet having a certain curvature, and is fixed to a part, corresponding to the backrest of the folding chair, of the oxford cloth; the second waist-rest portion 124 is a steel sheet having a certain curvature, and is fixed to a part, corresponding to the backrest of the folding chair, of the oxford cloth.

In using, the first backrest tube 101, the second backrest tube 102, the second upper connecting tube 109 and the second lower connecting tube 110 are moved outward so as to unfold the folding chair. Under the action of the first waist-rest portion 123 and the second waist-rest portion 124, a protruding portion is formed on the oxford cloth to properly support the waist of the user, so as to improve comfortableness for a user. During folding, the folding process can be achieved in only one step by pulling the second front-leg tube 107 and the second rear-leg tube 108 inward.

As shown in FIGS. 22 to 33, the embodiments of the present application further provide a folding chair. The folding chair includes a first intersecting tube including a first front-leg tube 105 and a first rear-leg tube 106 which are articulated to one another, a first U-shaped member 135 being sleeved on the first rear-leg tube 106; a second intersecting tube including a second front-leg tube 107 and a second rear-leg tube 108 which are articulated to one another, a second U-shaped member 136 being sleeved on the second rear-leg tube 108; a first backrest tube 101, on which a first through-hole bracket 111 is sleeved, and a bottom end of the first backrest tube 101 being articulated to the first U-shaped member 135; and a second backrest tube 102, on which a second through-hole bracket 112 is sleeved, and a bottom end of the second backrest tube 102 being articulated to the second U-shaped member 136. Specifically, arc-shaped protrusions for supporting the waist are respectively formed at an end, close to the first backrest tube 101, of the first front-leg tube 105 and an end, close to the second backrest tube 102, of the second front-leg tube 107. The arc-shaped protrusions include a first arc-shaped protrusion 139 and a second arc-shaped protrusion 140. The first arc-shaped protrusion 139 and the second arc-shaped protrusion 140 respectively form a first waist-rest portion and a second waist-rest portion which may fit a waist curve when the folding chair is unfolded.

The folding chair in the above embodiments further includes a first seat tube 131, a second seat tube 132, a first retractable tube 133, a second retractable tube 134, a first connecting component, and a second connecting component. Specifically, the first seat tube 131 is articulated to the bottom end of the first backrest tube 101 and the first front-leg tube 105. The second seat tube 132 is articulated to the bottom end of the second backrest tube 102 and the second front-leg tube 107. One end of the first retractable tube 133 is articulated to the first seat tube 131, and the other end thereof is articulated to the first front-leg tube 105. One end of the second retractable tube 134 is articulated to the second seat tube 132, and the other end thereof is articulated to the second front-leg tube 107. The first connecting component connects the first backrest tube 101 and the second backrest tube 102. The second connecting component connects the first retractable tube 133 and the second retractable tube 134.

In the folding chair of the embodiments of the present application, the first front-leg tube 105 and the second front-leg tube 107 are each provided with an arc-shaped protrusion for supporting the waist. The oxford cloth is covered on the first backrest tube, the second backrest tube and the second connecting component of the folding chair. When the folding chair is unfolded, the oxford cloth is completely spread, and the oxford cloth supported by the arc-shaped protrusions on the first front-leg tube 105 and the second front-leg tube 107, that is the first waist-rest portion and the second waist-rest portion, forms a backrest of the folding chair, and the oxford cloth supported by the first intersecting tube, the second intersecting tube and the second connecting component forms a chair seat of the folding chair.

In using, the folding chair is unfolded, and under the action of the arc-shaped protrusions of the first front-leg tube 105 and the second front-leg tube 107, a protruding portion is formed on the oxford cloth to properly support the waist of the user, thereby having the function of supporting the waist and improving comfortableness for a user.

In the above embodiments of the present application, the first connecting component and the second connecting component can be rigid connecting components, such as a connecting tube. Taking the first connecting component as an example, two ends of the connecting tube are respectively fixed to the first backrest tube 101 and the second backrest tube 102, and at this time, the first backrest tube 101 and the second backrest tube 102 can not perform a folding action. Furthermore, the first connecting component and the second connecting component can be components that can be unfolded and folded, such as connecting sheets with ends thereof being overlapped and articulated. Specifically, one of the connecting sheets is articulated to the first backrest tube 101, and the other connecting sheet is articulated to the second backrest tube 102. And, an elastic component having a clamping function is provided at articulated parts of the connecting sheets, and when it is required to fold the first connecting sheet and the second connecting sheet, the elastic component is pulled outward, then the first connecting sheet and the second connecting sheet can be folded.

In the embodiment of the present application, the first connecting component includes a first upper connecting tube 103 and a first lower connecting tube 104 which are articulated to one another at middle portions thereof. Specifically, a top end of the first upper connecting tube 103 is articulated to the first through-hole bracket 111, a bottom end of the first upper connecting tube 103 is articulated to the second rear-leg tube 108, a top end of the first lower connecting tube 104 is articulated to the second through-hole bracket 112, and a bottom end of the first lower connecting tube 104 is articulated to the first rear-leg tube 106.

The second connecting component includes a second upper connecting tube 109 and a second lower connecting tube 110 which are articulated to one another at middle portions thereof. Specifically, a top end of the second upper connecting tube 109 is articulated to an outer retractable tube of the first retractable tube 133, a bottom end of the second upper connecting tube 109 is articulated to an inner retractable tube of the second retractable tube 134, a top end of the second lower connecting tube 110 is articulated to an outer retractable tube of the second retractable tube 134, and a bottom end of the second lower connecting tube 110 is articulated to an inner retractable tube of the first retractable tube 133.

The top end of the first rear-leg tube 106 is extended to form a first armrest portion, and the top end of the second rear-leg tube 108 is extended to form a second armrest portion. Due to the arrangement of the armrest portions, a user can put his hands on the armrest portions.

The structures of the first retractable tube 133 and the second retractable tube 134 described above can refer to FIGS. 22, 24 and 25. Taking the first retractable tube 133 as an example, as shown in FIG. 22, when the folding chair is unfolded, the first retractable tube 133 is retracted, the inner retractable tube is completely covered by the outer retractable tube, and at this time, an entire length of the first retractable tube 133 reaches a minimum value. As shown in FIG. 24, when folding the folding chair, since the first seat tube 131 and the second seat tube 132 are lifted upward, the first retractable tube 133 is stretched, with the inner retractable tube being extended out of the outer retractable tube. As shown in FIG. 25, the folding chair is completely folded, the first retractable tube 133 is completely extended, and at this time the entire length of the first retractable tube 133 reaches a maximum value.

The first retractable tube 133 may be directly articulated to the first seat tube 131. Or, a third U-shaped member 137 may be sleeved on the first seat tube 131, the outer retractable tube of the first retractable tube 133 is articulated to the first seat tube 131 via the third U-shaped member 137, and the inner retractable tube of the first retractable tube 133 is articulated to the first front-leg tube 105 via a pin.

The second retractable tube 134 may be directly articulated to the second seat tube 132. Or, a fourth U-shaped member 138 may be sleeved on the second seat tube 132, the outer retractable tube of the second retractable tube 134 is articulated to the second seat tube 132 via the fourth U-shaped member 138, and the inner retractable tube of the second retractable tube 134 is articulated to the second front-leg tube 107 via a pin.

The tube members can be connected by riveting. Wherein, the intersecting tube members can be connected via rivets. For realizing the connection between one end of a tube member and a middle portion of another tube member, a U-shaped member may be articulated to the middle portion of the latter tube member, and the former tube member is articulated to the middle portion of the latter tube member via the U-shaped member.

Furthermore, compared with the prior art, the volume of the folding chair being folded in the embodiments of the present application is not significantly increased, referring to FIGS. 22 and 25.

As shown in FIGS. 22 to 25, in the folding chair according to the fifth embodiment of the present application, after being bent, the first arc-shaped protrusion 139 on the first front-leg tube 105 is directly welded on the top end of the first front-leg tube 105 to form an integral structure; and after being bent, the second arc-shaped protrusion 140 on the second front-leg tube 106 is directly welded on the top end of the second front-leg tube 106 to form an integral structure.

As shown in FIGS. 26 to 29, in the folding chair according to the sixth embodiment of the present application, the first front-leg tube 105 and the first arc-shaped protrusion 139 thereon are formed by bending one tube member, and the second front-leg tube 106 and the second arc-shaped protrusion 140 thereon are formed by bending one tube member. Other structures of the folding chair can be referred to the fifth embodiment.

As shown in FIGS. 30 to 33, in the folding chair according to the seventh embodiment of the present application, two ends of the first arc-shaped protrusion 139 formed by a bended tube member are welded onto the first front-leg tube 105, two ends of the second arc-shaped protrusion 140 formed by a bended tube are welded onto the second front-leg tube 107. Other structures of the folding chair can be referred to the fifth embodiment.

The folding chair provided by the present application is described in detail hereinbefore. The principle and the embodiments of the present application are illustrated herein by specific examples. The above description of examples is only intended to help the understanding of the method and the spirit of the present application. It should be noted that, for the person skilled in the art, many modifications and improvements may be made to the present application without departing from the principle of the present application, and these modifications and improvements are also deemed to fall into the protection scope of the present application defined by the claims. 

1. A folding chair, comprising: a first backrest tube, on which a first through-hole bracket is sleeved; a second backrest tube, on which a second through-hole bracket is sleeved; a first connecting component connecting the first backrest tube and the second backrest tube; a first intersecting tube comprising a first front-leg tube and a first rear-leg tube which are articulated to one another; a second intersecting tube comprising a second front-leg tube and a second rear-leg tube which are articulated to one another; and a second connecting component connecting the first intersecting tube and the second intersecting tube; wherein the folding chair further comprises a first waist-rest portion and a second waist-rest portion which are symmetrically arranged, and are configured to fit a waist curve when the folding chair is unfolded.
 2. The folding chair according to claim 1, wherein the first connecting component comprises a first upper connecting tube and a first lower connecting tube which are articulated to one another at middle portions thereof; and the second connecting component comprises a second upper connecting tube and a second lower connecting tube which are articulated to one another at middle portions thereof.
 3. The folding chair according to claim 2, wherein the first front-leg tube comprises a top end articulated to the first through-hole bracket and a bottom end fixedly provided with a third lower bracket; and the first rear-leg tube comprises a top end provided with a first upper bracket and a bottom end articulated to the first backrest tube via a first lower bracket; and the second front-leg tube comprises a top end articulated to the second through-hole bracket and a bottom end fixedly provided with a fourth lower bracket; and the second rear-leg tube comprises a top end provided with a second upper bracket and a bottom end articulated to the second backrest tube via a second lower bracket.
 4. The folding chair according to claim 3, wherein the first upper connecting tube comprises a top end articulated to the first through-hole bracket and a bottom end articulated to the second lower bracket; and the first lower connecting tube comprises a top end articulated to the second through-hole bracket and a bottom end articulated to the first lower bracket; and the second upper connecting tube comprises a top end articulated to the first upper bracket and a bottom end articulated to the fourth lower bracket; and the second lower connecting tube comprises a top end articulated to the second upper bracket and a bottom end articulated to the third lower bracket.
 5. The folding chair according to claim 4, wherein the top end of the second upper connecting tube is extended to form a first armrest portion, and the top end of the second lower connecting tube is extended to form a second armrest portion.
 6. The folding chair according to claim 4, further comprising a first waist-rest tube and a second waist-rest tube, wherein the first waist-rest portion is an arc-shaped protrusion provided on an upper portion of the first waist-rest tube, and the second waist-rest portion is an arc-shaped protrusion provided on an upper portion of the second waist-rest tube.
 7. The folding chair according to claim 6, wherein the first waist-rest tube comprises a bottom end articulated to a first sliding block, and a middle portion articulated to an end, close to the first through-hole bracket, of the first upper connecting tube, and the first sliding block is sleeved on an end, close to the first lower bracket, of the first lower connecting tube; and the second waist-rest tube comprises a bottom end articulated to a second sliding block, and a middle portion articulated to an end, close to the second through-hole bracket, of the first lower connecting tube, and the second sliding block is sleeved on an end, close to the second lower bracket, of the first upper connecting tube.
 8. The folding chair according to claim 6, wherein the first waist-rest tube comprises a bottom end articulated to a first sliding block, and a middle portion articulated to an end, close to the first through-hole bracket, of the first front-leg tube, and the first sliding block is sleeved on an end, close to the first lower bracket, of the first rear-leg tube; and the second waist-rest tube comprises a bottom end articulated to a second sliding block, and a middle portion articulated to an end, close to the second through-hole bracket, of the second front-leg tube, and the second sliding block is sleeved on an end, close to the second lower bracket, of the second rear-leg tube.
 9. The folding chair according to claim 6, wherein the first waist-rest tube comprises a bottom end articulated to a first sliding block, and a middle portion articulated to an end, close to the first through-hole bracket, of the first front-leg tube, and the first sliding block is sleeved on the first backrest tube; and the second waist-rest tube comprises a bottom end articulated to a second sliding block, and a middle portion articulated to an end, close to the second through-hole bracket, of the second front-leg tube, and the second sliding block is sleeved on the second backrest tube.
 10. The folding chair according to claim 4, further comprising an oxford cloth covered on the first backrest tube, the second backrest tube and the second connecting component.
 11. The folding chair according to claim 10, wherein the first waist-rest portion comprises a first woven strip and a first steel sheet, the first steel sheet is bent at a preset angle by the first woven strip, and the first waist-rest portion is fixed at a part, corresponding to a backrest of the folding chair, of the oxford cloth; and the second waist-rest portion comprises a second woven strip and a second steel sheet, the second steel sheet is bent at a preset angle by the second woven strip, and the second waist-rest portion is fixed at a part, corresponding to the backrest of the folding chair, of the oxford cloth.
 12. The folding chair according to claim 10, wherein the first waist-rest portion is a steel sheet having a certain curvature and is fixed at a part, corresponding to a backrest of the folding chair, of the oxford cloth; and the second waist-rest portion is a steel sheet having a certain curvature, and is fixed at a part, corresponding to the backrest of the folding chair, of the oxford cloth.
 13. The folding chair according to claim 2, wherein the first waist-rest portion is an arc-shaped protrusion provided on an end, close to the first backrest tube, of the first front-leg tube, and the second waist-rest portion is an arc-shaped protrusion provided on an end, close to the second backrest tube, of the second front-leg tube; a top end of the first front-leg tube is articulated to the first through-hole bracket, and a top end of the second front-leg tube is articulated to the second through-hole bracket; and a first U-shaped member is sleeved on the first rear-leg tube, and a bottom end of the first backrest tube is articulated to the first U-shaped member; and a second U-shaped member is sleeved on the second rear-leg tube, and a bottom end of the second backrest tube is articulated to the second U-shaped member.
 14. The folding chair according to claim 13, wherein a top end of the first rear-leg tube is extended to form a first armrest portion, and a top end of the second rear-leg tube is extended to form a second armrest portion.
 15. The folding chair according to claim 13, further comprising a first seat tube articulated to the bottom end of the first backrest tube and the first front-leg tube; a second seat tube articulated to the bottom end of the second backrest tube and the second front-leg tube; a first retractable tube comprising one end articulated to the first seat tube and the other end articulated to the first front-leg tube; and a second retractable tube comprising one end articulated to the second seat tube and the other end articulated to the second front-leg tube.
 16. The folding chair according to claim 15, wherein the first upper connecting tube comprises a top end articulated to the first through-hole bracket, and a bottom end articulated to the second rear-leg tube; and the first lower connecting tube comprises a top end articulated to the second through-hole bracket, and a bottom end articulated to the first rear-leg tube; and the second upper connecting tube comprises a top end articulated to an outer retractable tube of the first retractable tube, and a bottom end articulated to an inner retractable tube of the second retractable tube; and the second lower connecting tube comprises a top end articulated to an outer retractable tube of the second retractable tube, and a bottom end articulated to an inner retractable tube of the first retractable tube.
 17. The folding chair according to claim 16, wherein the outer retractable tube of the first retractable tube is articulated to the first seat tube via a third U-shaped member, and the inner retractable tube of the first retractable tube is articulated to the first front-leg tube via a pin; and the outer retractable tube of the second retractable tube is articulated to the second seat tube via a fourth U-shaped member, and the inner retractable tube of the second retractable tube is articulated to the second front-leg tube via a pin.
 18. The folding chair according to claim 13, wherein the arc-shaped protrusion on the first front-leg tube and the first front-leg tube are welded to form an integral structure; and the arc-shaped protrusion on the second front-leg tube and the second front-leg tube are welded to form an integral structure.
 19. The folding chair according to claim 13, wherein the first front-leg tube and the arc-shaped protrusion on the first front-leg tube are formed by bending a tube member, and the second front-leg tube and the arc-shaped protrusion on the second front-leg tube are formed by bending a tube member.
 20. The folding chair according to claim 13, wherein the arc-shaped protrusion on the first front-leg tube is formed by bending a tube member and comprises two ends welded on the first front-leg tube; and the arc-shaped protrusion on the second front-leg tube is formed by bending a tube member and comprises two ends welded on the second front-leg tube. 